If you have following drive systems:
Traditional AC motor, frequency converter and gear box combination
Variable speed DC drive system with gear box
and if you want to increase system reliability while you can reduce following cost related items:
energy consumption
plant engineering hours
pump skid and foundation size
maintenance costs
spare part inventories
you should consider to switch to direct drive system. The direct drive system working voltage: 460v, 600, 700-1400, 1500-2500. 3300, 4160, 6000. Power: 55kw-630kw